Product Reviews

As hard disk capacities increase exponentially so prices keep on dropping, leading some to believe they're a better medium for backup than tape. Dantz now considers them highly suited to server backup and even practical for securing SQL and Exchange servers, so has released a new version of its Retrospect backup software just for this purpose. The company goes further by claiming that with just two FireWire or USB 2 external hard disks you can implement an off-site backup strategy, presumably by swapping out each drive on a daily or weekly basis.

In reality, Retrospect Disk-to-Disk for Windows (RDDW) is merely Dantz's standard backup software but with support for tape drives removed. It's not new either, as we first saw this software in a different guise some years ago when it was launched as Retrospect Express (see issue 84, p161) and was intended for those who wanted to back up their data to devices such as CD-R/RW, DVD, MO (magneto optical) or hard disk. Strangely, the Express version didn't last long, as it was dropped within a year in favour of Retrospect Professional 5.6; this was aimed at home users and small businesses for backing up one local and two non-server remote systems and included support for tape drives.

This time, Dantz has licensed the base product to secure a single Windows server to removable media such as CD-R/RW, DVD-RAM, MO and, of course, removable hard disks. The product can be upgraded easily, as it supports all of Dantz's optional add-ons. You can include remote workstations in the backup strategy by installing Retrospect agents on them and buy additional agents for SQL Server and Exchange Server.

Installation for Retrospect has always been a swift affair and RDDW is no different. The first thing of note is that the standard backup-and-restore features are all present, so you'll find plenty of options with which to play. The biggest difference between Retrospect and conventional backup software is that it doesn't mess around with archives during backup, as these aren't used to determine whether a file needs to be secured. Retrospect compares the files it has

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already backed up to those on the source hard disk and, if the same file is already listed, it won't copy it again. It uses Snaphots to allow hard disks to be restored to their original condition in the event of a failure. Renamed as Progressive Backup, this feature has a number of advantages, particularly when multiple backup copies are required for storing data onsite and offsite.

The main interface is a tidy affair, and a wizard takes you through the process of creating your backup tasks. Dantz has also added a decent job monitor that allows you to view all jobs whether active, scheduled or waiting, along with history and alert logs. With hard disks as the primary backup target, NAS (network attached storage) appliances naturally come into the equation, but you'll find a number of limitations. NDMP (network data management protocol) isn't supported, so Retrospect can only access remote systems for backup if the client is installed first. Consequently, you can only back up from NAS appliances that are Windows powered and accessed via Terminal Services or Remote Desktop. Note also that if you plan to include the Windows Server 2003 Volume Shadow Copy service in the backup scheme, you'll need the optional open file backup agent. However, things get much easier if you use a NAS appliance as a backup destination, since Retrospect views it the same as any other network volume.

Retrospect is a good candidate for backup in small to medium-sized businesses, but it will take a lot more to convince us that hard disks are the way to go. With hard disk prices at an all-time low, overall storage costs are coming into line with tape, but to get the best value you'll need to go for 200GB or larger hard disks. Few small businesses are going to be backing up this amount of data on a daily basis, leaving most of this available storage space wasted. However, our biggest issue is using removable hard disks in a rotating off-site storage strategy. We used a Maxtor Personal Storage 5000XT (see issue 101, p120) for securing data from a single workstation and removing it off-site on a daily basis, but after less than six months the 250GB hard disk failed completely. Furthermore, thanks to the constant plugging and unplugging, the USB interface on the 5000XT gradually worked loose and frequently failed to function during the latter part of this test.

We've always had a lot of respect for Dantz's backup software, as it offers a good range of features at an affordable price and comes with plenty of optional extras. At first glance, hard disks look worthy of consideration for backup, but our long-term tests indicate they don't take too kindly to being transported between locations on a regular basis.